Cam and jack arrangements for flatbed transfer knitting machines



March 17, 1959 A.

E. PRIOR CAM AND JACK ARRANGEMENTS FOR FLAT-BED TRANSFER KNITTING MACHINES Filed Nov. 21, 1956 3 Sheets-Sheet 1 2g 25 /3 36 60 23 v I o 22 INVE VWR 44 AN mwmm mm JWW ,wramve 5 March 17, 1959 I A E PRIOR 2,877,634

CAM AND JACK ARA'NcEMENTs FOR FLAT-BED TRANSFER KNITTING MACHINES Filed NOV. 21, 1956 3 Sheets-Sheet 2 March 17, 1959 A.- E. PRIOR v2,877,634

CAM AND JACK ARRANGEMENTS FOR FLAT-BED TRANSFER KNITTING MACHINES Flled Nov. 21, 1956 5 Sheets-Sheet 5 3 km a F. 3 T m H 3 M M a m Afro/W 75 j M/VEA/TM Ann/v mm mm A n v65; uzttzr i i I Al: 55: wzF=zz .A 1 o 55: 58; "B 50 United States Patent CAM AND JACK ARRANGEMENTS FOR FLAT- BED TRANSFER KNITTING MACHINES Allan Edward Prior, Bellevue Hill, near Sydney, New South Wales, Australia This invention relates to flat-bed transfer knitting machines of the kind having twin beds grooved to accommodate horizontally opposed jacks, either of which (in each opposed pair) is able to engage and actuate a double ended needle aligned therewith. Each needle is guided in its knitting or transfer movements by the bed grooves of the two jacks associated with that particular needle; and the jacks are operated to effect the required needle movements by cams on a carrier (or so-called ljcgm box) which is slidable longitudinally of the twin I e s.

In machines of the kind referred to, one of the jacks associated with a single needle may be called the active jack and the companion but opposed jack then becomes an idling jack. That jack of the two which, for the time being, is active, operates the needle in its knitting motion by engagement of a draw hook and a push shoulder on the jack with the (for time being) inner or nonknitting hooked end of the needle. The free end of the needle is then the knitting end, and the jack has an upstanding butt thereon engageable by the knitting cams on the underface of the carrier which spans both of the beds having a set of knitting cams for each.

If knitting is started and continued with active jacks all in one bed, the resulting fabric will consist wholly of plain stitches (or all purl stitches if viewed from the opposite or wrong side of the fabric) but if one or more needles are transferred from the starting bed into the companion bed so that its active jack becomes an idler and the opposed former idler jack becomes active, the next stitch by that needle will be purl relative to the otherwise plain or right side of the fabric.

It follows that as most of the patterning requirements for a knitted fabric consist in the selective distribution and frequency of purl stitches relative to plain stitches, the major or basic manipulation for patterning purposes is transfer and return of selected needles from one bed to the other; or, in other words, selecting which jacks in the two beds shall be active in performing any single row of stitches.

Previous knitting machines of the kind under discussion have, of course, employed the above described transfer principle for patterning knitted fabric; but the previous machines while eifective within the work compass for which they are designed, are remiss in several respects. For example, transfer of needles from one bed to the other is effected manually or only with expensive jacquard or like relatively complex mechanisms; needles can only be transferred in one direction during a single working pass of the cam box thus placing a severe limitation on. the number and variety of patternings which can be knitted on the machine; stitch size has to be varied by at least two separate cam adjustments; and yarn infeed to the cam box is by way of lost-motion or lag-feed devices in order to ensure proper presentation of the yarnto theneedles, the lost-motion or lag-feed devices being complex and the cause of relatively freice qnent breakdowns and need for frequent and extensive servicing.

The object of thepresent invention is to overcome the stated disabilities in a simple and inexpensive manner, by the provision of a cam box and jack arrangement which enables:

(a) jacks, associated with needles to be transferred, to be manually or otherwise selected in known manner and then automatically cause transfer of the needles associated with the selected jacks from one bed to the other (in either direction) during a single working stroke of the cam box, and wholly by use of the ordinary knitting cams thereof. That is, without necessity for special jack release cams or the like;

(b) knitting ranges of different patternings greatly in excess of those previously obtainable with earlier machines of like kind;

(1:) selection of stitch size by operation of only a single control element;

(d) direct infeed of yarn to the centre of the cam box without necessity for lost-motion or like lag-feed devices; and

(e) generally improved and simple operation and construction of the machine. That is to say, the present machine by comparison with previous machines of like kind, is mechanically less complex in both construction and use.

In the machine subject hereof the opposed needle beds and the cam box runways may be of more-or-less conventional design; and the double ended needles employed can be of the common hook and hinged-latch type.

The major characteristic of the present invention con sists in the provision, in a knitting machine of the knd indicated, of means enablng transfer of needles from either bed to the other during a single pass of the machine carrier; such means comprising a fulcrum hump on the under edge of each jack, a clearance bight in the upper edge of each jack, and at least two keeper bars which extend longitudinally of and project downwardly from the underside of the carrier, the keeper bars being so positioned that during needle transfer, resulting froma pass of the carrier, one bar prevents rising of the foreend of a taking jack about its fulcrum hump, while the other overlies the clearance bight of a selected relinquishing jack. 1

An example of the invention is illustrated in the draw-; ings herewith.

Fig. 1 is a plan of a knitting machine on a somewhat. reduced scale and incompletely detailed;

Fig. 2 is an end view of the machine shown in Fig. l. on a slightly larger scale, indicating the manner in which, the machine is to be supported on a table, bench or the like;

Fig. 3 is a plan of the carrier or cam-box drawn on a still larger scale; E

Fig. 4 repeats Fig. 3 but with a cover plate removed:

Fig. 5 is an incomplete sectional end elevation taken on line 55 in Fig. 4;

Fig. 6 is a sectional plan taken on line 66 in Fig. 5,- being a schematic lay-out, viewed from above, of those parts which are disposed under or project downwardly from the underface of the carrier;

Each of Figs. 7 to 11 is a transverse sectional e'nd. elevation through the machine bed illustrating the various stages in the transfer of a needle from one bed to the; other; i Fig. 12 is a plan of a portion of the twin beds in effect being an enlarged representation of the left-handend; portion of Fig. l.

Each of Figs. 7 to 11 may be regarded as a section taken on line A--A in Fig. 12. 1

.The twin. beds each. consistof, a plate 13,

are respectively slidable to impart knitting motion to double ended needles 18 substantially in known manner.

The two plates 13 and 14 are fixedly mounted in moreor-less conventional manner in a frame indicated at 19.

Frame 19 has flange-like portions 20 thereon (see Fig. 2)

to enable the machine as a whole to be clamped to a table or the like so that the knitting drop line 21 is clear of the table edge. The frame 19 has flanged portions 22 which constitute a runway for the carrier indicated generally by 23; the carrier having longitudinal edge flanges 24 which engage under the frame iianges 22.

The carrier may carry a conventional row counter indicated at 25 which is operable by a striker cam 2.6 fixed on the bed frame.

The jacks for the two beds are similar and (see mainly Fig. 11) each comprises a plate-like body 27 adapted to fit neatly but slidably, and edgewisely, in a bed groove. Each jack has a forwardly projecting latch guard finger 28 which when under a stationary transfer bar 29 on the bed, or under a keeper bar 30 or 31 on the carrier, prevents rising of the front end of the jack.

The under edge of each jack has a recess 32 therein which at its rear constitutes a needle pushing shoulder, and is forwardly arcuate so that when the forward end of the jack is free to rise, a needle hook in the recess is able to recede from the jack and leave it standing.

The under edge of the jack body is obtusely angled so that it is substantially centrally slightly protuberant. The protuberance 33 constitutes a fulcrum hump which by resting on the floor of a bed groove enables the jack (when not otherwise restrained) to rock, through a few degrees of angle, thus permitting the recessed portion (32) of the jack to rise sufiiciently to enable a needle hook therein to be withdrawn from engagement therewith, thus to leave the jack standing (as referred to above) and thereby transform it from an active jack to an idler when the needle is taken from it.

The upper edge of-each jack shank has an upstanding butt 34 thereon for engagement with the knitting cams in known manner, and forwardly of the butt this upper edge is slightly down-trended to provide a mechanical clearance bight 35 which permits the jack to rock (as referred to above) when this bight is under the keeper bar 30 on the carrier.

The cam-box or carrier .23 is a plate-like body having a handle 36 fixedly mounted thereon to enable the carrier to be manually moved to-and-fro along the twin beds. The underside of the carrier has a pair of runway grooves 37 formed therein slidably to receive the tongued edges 38 (see Fig. of a yarn threader plate 39. This plate has a central yarn infeed hole 40 towards which yarn may freely run by way of either end portion of a groove 41 in the upper face of the plate. The plate 39 is normally retained in its knitting position (as shown in Figs. 3 to 5) by small upstanding lugs 42 able to abut the edges of the carrier body. The ends of the plate 39 which carry the lugs 42 are sufficiently flexible and sufliciently spaced from the tongued edges 38, as to enable removal of the plate 39 from the carrier by depression of one end of the plate followed by endwise extraction from the carrier. It will be seen that the yarn threader plate arrangement provides the cam-box with a centrally disposed yarn infeed hole (40) which by reason of its being central relative to the off-centre disposition of the knitting cams (as described below) ensures effective .infeed and laying down of the yarn on to the needles without necessity for lost-motion or lag-feed means otherwise necessary to ensure efiective presentation of the yarn to the needles.

There are two sets of cams on the underside of the carrier. These cam sets are respectively associated with the two machine beds and they are substantially .identical, one set being, in eifect, the mirrored image of the other;

and, in each set the camming surfaces on one side of the transverse centre line of the carrier (parallel to the bed grooves) are practically a mirrored replica of those on the other side of that centre line.

Each of the two cam groups comprises a number of strip cams which are fixed on the underside of the carrier, and a number of movable cams which are pivotally or slidabl-y mounted on the underside of the carrier. Also there are the keeper bars 39 and 31 which are not cams in the sense of that term as used herein because they are not adapted to be ridden against by the jack butts 34, being present merely to hold down the front ends (28) of the jacks (as shown by the right-hand jacks in Figs. 9 and 16) during ordinary knitting motion thereof. On looking at Figs. 9 and it) it might be Wondered why the keeper bars 31 do not appear therein. This is due to the fact (as will be seen later herein) that Figs. 9 and 10 show steps in the process of needle transfer, and such transfer occurs while the needle being transferred .lies opposite that part of a bar 3t! in which rising movement of its relinquishing jack will not be impeded by bar 31. In other words, needle transfer takes place within a span such as that represented by B in Fig. 6, into which the bars 31 do not effectively extend.

The cams are able to guide the jacks along three different paths by bearing against the jack butts 34.

These three paths may be identified as:

(a) a transfer track; (b) a stitch forming track, and

(c) an out-of-work track.

These tracks are marked (a, b and c) in Fig. 6; being there shown for one set of cams and then only for leftward movement of the carrier as indicated by the rightwardly directed arrows.

Before proceeding with a description of the earn assembly, it should be kept in mind that the needles are operated .by the cams (through the agency of the jacks) in a substantially conventional manner insofar as the actual formation of stitches is concerned, the needles with their latches open first clearing a previously formed stitch and then having the yarn laid thereon. The needle is then drawn down, thus hooking the laid yarn as a loop or new stitch while the previously formed stitch closes the needle latch as the new stitch is formed and passes off the needle to become knitted. The needle is then pushed up so that the loop on the hook re-opens the latch by passing over it on to the shank of the needle in readiness for thenext stitch forming.

It will be noticed that the needle is referred to above as moving down and up. Actually, of course the needle movement is horizontal, and these terms are used purely for descriptive convenience, up being used in the sense of towards the longitudinal centre line of the twin bed, and down away from that centre line. The terms .left and right are similarly used herein for descriptive convenience.

As previously indicated the two cam groups are substantially symmetrical about the longitudinal centre line of the twin beds; that is, in the direction of carrier travel. Also, the two halves of each cam group are substantially symmetrical about a transverse centre line; that is, a centre line at right angles to the direction of carrier travel. The yarn infeed hole 40 is in the middle of the carrier at the intersection of the two mentioned centre lines.

In a'preferred form of the invention, each cam group comprises a centre flap or swivel leaf cam 43 freely pivoted about a bolt 44 fixed to the carrier. Cam 43 is flanked on either side of two jack return cams 45, 46 and .two stitch forming cams 47, 48. The earns 45, 46 are strip cams fixed to the carrier by being integral therewith or otherwise. The cams 47, 48 are movable towards or away from the longitudinal centre line .of the carrier to enable the knitting tension (i. e. the size of the stitch .loops formed by needle movement resulting from a jack riding the cams 47, 48) to be varied as required. This adjustability of the cams 47, 48 may be provided for by mounting them by pins 49, 50 on runner blocks 51, 52 longitudinally slidable in guide slots 53, 54. The runner blocks 51, 52 are held against a follower 55 by tension springs 56. These springs are anchored to the runner blocks; and, at their other ends, to a pin 57 fixed to and upstanding from a guide block 58 fixed on the carrier body. The followers 55 are slidable about the guide blocks 58 and their inner ends ride a two throw tension adjusting cam 59 which is fixed to a finger adjustment ring 60 rotatably mounted under the handpiece 36 and on the boss 61 thereof, but above the cover plate 62 (shown in Fig. 3 but not in Fig. 4). The guide blocks have the bolts 44 extending therethrough thus enabling the cover plate 62 to be held in position by nuts 63.

The remaining cams of the system are the stationary guard cams 64, 65 and 66; and the stitch clearing cams 67, 68. The cams 67, 68 are pivotally mounted on pivot pins 69 fixed to the underside of the carrier, and each has an upstanding peg 70 which projects upwardly through a hole 71 in the carrier body and has a light loading spring 72 attached thereto. The effect of the springs 72 is to influence the cams 67, 68 to remain in or assume the full line normal knitting positions shown in Fig. 6.

The cams 67, 68 may be held open (out of their normal knitting positions) as indicated by dotted line position of the cam 67 in the top left corner of Fig. 6, by pull-straps 73 which hook about the cams and are respectively connected to finger buttons 74, 75, 76 and 77 which are slidable in slots 78 with sufiicient frictional tightness to hold a selected stitch forming cam open, notwithstanding the influence of its spring 72.

In ordinary knitting the number of working needles required is selected substantially in known manner. This selection brings the butts of the jacks for the selected needles into line with one of the stitch-forming tracks as indicated by b in Figs. 6 and 12. In ordinary stitch forming the jack butts follow track b and (assuming the carrier is at the right end of the beds and is moved leftwardly) each jack traverses this track by first entering a substantially horizontal track portion between the adjacent left ends of the cams 64 and 66. The entered butt then rides upwardly and rightwardly against the left-hand stitch clearing cam 67. At the top of this stitch clearing cam the needle hooked to the jack reaches the highest point of the stitch forming track, and at this point the previously made stitch passes over the needle latch in operation thus opening it in readiness for its hook to receive the next yarn portion to be laid thereon and at the same time clearing the made stitch. The needle butt then proceeds slightly downwardly but substantially horizontally until it meets the swivel leaf 43 which it pushes to the position shown in Fig. 6 (near the bottom of the figure). (It will be noticed that in this description the jack butt is referred to as travelling through the cam group, whereas the jack is actually stationary, except for its movement in the direction of its own length, and the cam group travels past it. The motion of cams and needles is however purely relative and therefore the mode of description, adopted for descriptive convenience, gives a simpler account of the camming actions.)

When the jack butt arrives at the centre region of cam 43, the yarn extending through centre hole 40 is laid on the needle belonging to that butt and the cam 43 then sends the jack and its needle downwardly until the apex of the stitch forming cam 48 is reached. In this motion the stitch is formed as a loop the size (and hence the looseness) of which is governed by the adjustment effected by use of the finger ring 60 to turn the tension adjusting cam 59. In doing this the needle latch is closed and the previous stitch relinquished. After passing the lowermost point or apex of the right stitch forming cam, the butt is raised (by riding the right end of cam 66, and'by clicking past the right, spring-loaded; stitch clearing cam 68) back to the level at which it entered the left end of the cam-group in readiness for an oppositely directed negotiation of a stitch forming track being the mirrored image of that marked 12.

In the next (reverse) working stroke of the carrier the above described butt progress along the stitch forming track is repeated from right to left, the two tracks being coincident at the two ends and having a common cross-over point under the centre cam 43.

Fig. 7 shows the active jack (engaged with needle 18) and the companion idler jack in ordinary knitting disposition; that is, prior to selection for transfer of the needle.

When the needle is to be transferred into the opposite bed (to knit a purl stitch) its jack is manually pushed up its bed groove until the jack butt bears against the related transfer bar 29, as shown in Fig. 8. This puts the selected butt in a track "a. This selected jack is still an active jack inasmuch as it still has its needle hooked to it; and, in being pushed up it sends its needle closer to the companion idler jack in the opposite bed which during the previous row of knitting simply idled its way along the stitch forming track of the opposite cam group, moving in the same way (but ineffectively) as the active jack.

When the carrier (moving to the left) reaches the selected jack, the jack butt enters the transfer track by riding over that portion of cam 64 which corresponds to span B. At the same time the opposite idler jack, riding in the opposite stitch forming track, mounts the opposite left stitch clearing cam to a point where the bight 35 of the opposite jack is under the opposite transfer bar 29.

Thus the inner end of the idler jack is able to rise and its recess 32 engage over what, until the transfer actioncommenced, was the free or knitting end of the needle.

Both opposed jacks now have their recesses respectively engaged over the needle books.

The opposite jack then starts to withdraw from the first jack by reason of its butt riding the lower face of its cam 64 (lower is still being used in the sense of further taking jack is prevented from rising (as shown in Fig.

9) by reason of its latch guard finger being under the" span B portion of its keeper bar 30 but the first or re linquishing jack has its bight 35 under its keeper bar. and therefore the relinquishing. jack is free to rock about.

its fulcrum hump 33 while the taking jack isnot (see Fig. 10).

the needle into the opposite bed; and the first jack, by its momentary freedom to rock, relinquishes its hold on the needle. In this manner the needle is transferred and the taking jack becomes the active jack (see Fig. 11). Simultaneously, the first jack becomes an idler and as it continues along track (1" it engages its cam 45 and by it is sent towards the centre cam 43. That cam guides the relinquishing butt into the stitch forming track into which at that point, the transfer track merges. The newly established idler will then continue to traverse its stitch forming track inefiectively, until such time as the now active opposite jack is pushed up for a return transfer.

The out-of-work track "0 is that in which the butts of unworking jacks are normally placed.

In the foregoing description the knitting and transfer actions have been described as they occur; that is, with all of the buttons 74 to 78 disposed in the in position which causes the jack butts to ride the inner faces of the cams 67 and 68 to effect stitch clearance. Clearly, if the buttons, or any of them, are in the out position (shown dotted for button 76 in Fig. 4) stitch clearance by the cams concerned will not occur: Such cams then Thus, continued withdrawal movement of the taking jack, along its stitch forming track, draws being in the dotted position shown 'for the cam '67 near the top of Fig. 6. This ability is of importance in permitting various knitting effects, by reason of the fact that any stitch clearing camwith its button out will allow jack butts to pass through the carrier Without clearing a stitch or without taking yarn for formation of a new stitch, the original stitch remaining on the needle book. The uses of this provision will be apparent to those skilled in the art; for example, by having two diagonally opposite buttons out the machine will knit circular fabric, by having only one button out half cardigan stitch may be knitted, provided the stitch clearing cam and the stitch forming cam associated with the pulled out button are so formed that (without interfering with normal operation) they provide clearance for a needle butt to proceed uninterruptedly in a straight line to the centre flap cam 43. In short, any patterning which requires a needle to be non-working during one or more passes of the carrier may be effected by operation of one or more of .the four buttons 74 to 78. If desired, these buttons may be employed to give what is in effect an additional knitting track. This can be done by pushing selected jacks upwardly until their butts are against the transfer bar 29 for the particular bed, at the same time making sure that the potential taking jacks in the opposite bed are moved to non-working position thus to ensure against needle transfer actually taking place. By doing this the needles of the selected jacks will knit to the exclusion of all those not so selected, provided the two buttons related to the operative cam group are both open if the non-knitting of unselected needles is required during both right and left passes of the carrier; or, only one button is open if non-knitting is required in only one carrier direction.

It will be understood that although only the span B portions of the keeper bars 30 are efiective during needle transfer, the remainder of those bars and also those numbered 31, are preferably present in order to hold down the front ends of the jacks during knitting thus to ensure against unwanted relinquishrnent of a needle or other undesirable jack movement by bounce or otherwise. In this connection .it will be appreciated that rapid working'may'sometimes cause a needle latch to bounce or flip into closed position when it should :remain open. To guard against this, the yarn threader plate 39 may have brush-like bristle bunches 79 (see Fig. 5) on its underface: These bristles being placed to align with those positions in whichstitch clearance takes place so that in the event of a latch :flipping up it will strike the bristles and thus fall backinto open position.

Itwill be appreciated that although transfer bars such as 29 are preferably present almost to the point of being essential because of their usefulness in holding down 8 jack front ends and in constituting a gauge when placing jacks in the transfer tracks; these bars could be omitted by relying on the ends of the jacks forwardly of the fulcrum humps being heavier than the rear portions, and by gauging jack transfer position by other means or simply by visual judgment.

I claim:

1. A flat-bed transfer knitting machine comprising opposingly grooved twin beds, two transfer bars respectively fixed on said beds across the grooves therein, a plurality of jacks slidable in said grooves and each having a fulcrum hump on its under edge and a clearance bight and an operating butt on its upper edge, a plurality of needles operable in said grooves by engagement with recesses in the fore-ends of said jacks, a carrier which is slidable longitudinally of said beds, cams on .said carrier able to engage said butts thereby to effect knitting movements of said needles, and at least two keeper bars so positioned on said carrier that during needle transfer from one bed to the other resulting from selection of a relinquishing jack by placement of its butt against one of said transfer bars and from a subsequent pass of said carrier, one .Of said bars prevents rising of the fore-end of a taking jack about its fulcrum hump, while the other overlies the clearance bight of said relinquishing jack; said cams comprising, for each of said beds, a central swivel leaf cam, a pair of adjustable stitch forming cams and a pair of adjustable stitch clearing cams symmetrically flanking said swivel leaf cam, and a plurality of stationary cams for guiding jack butts into contact with the other cams herein mentioned.

2. A knitting machine according to claim 1 wherein said stitch forming cams are each rectilinearly adjustable by means of a runner block slidably mounted on said carrier and whereon the cam is fixedly mounted, a tollower slidably mounted on said carrier, a throw cam rotatably mounted on said carrier, and spring means for holding said block against said follower and said follower against said throw cam.

3. A knitting machine according to claim 1 wherein said stitch clearing cams are each pivotally mounted on said carrier and each is furnished with a loading spring tending to hold it in stitch clearing position and means enabling it to be frictionally .held out of that position.

References Cited-in thefile of this patent UNITED STATES PATENTS 708,786 Stoll Sept.,9, 1902 2,644,323 Zimie et al July 7,.l953

FOREIGN PATENTS 259,305 Germany May '3, 1913 387,056 Germany Dec.'20, 1923 

